The present invention pertains to a cyclone separator, which has as the principal components a spiral housing with inlets for raw material and separator gas, a separator wheel, a ring of vanes, and outlets for coarse and fine particulate matter as well as the separator air. The present invention is a novel design of such a cyclone separator, in which it is possible to carry out an operating method which fundamentally differs from the prior art operating methods and provides particularly good separation results without extra expense for additional structures.
However, it seems best for the understanding of the present invention to use German Offenlegungsschrift No. DE-OS 24,26,295 as the starting point, because the design of a cyclone separator according to the present invention seems to differ only slightly from a cyclone separator according to this prior-art reference, but the completely different mode of operation of a cyclone separator according to the present invention can be explained particularly well in comparison with this prior art.
DE 24,26,295, which is the closest prior art, is based on a cyclone separator, in which the material to be separated is introduced tangentially to the inner circle of a stationary vane ring with adjustable vanes, to the outer circle of which the separator air is tangentially introduced. The front walls of the separation space surrounded and delimited by the vane ring are rotatable just as the material to be separated in order to reduce frictional losses. The vanes of the vane ring are dimensioned and adjustable such that the material to be separated is separated into coarse matter and fine particulate matter in the separation space. The coarse matter is fed, near the inner circle of the vane ring, to a strip-off edge and is separated from the area of the fine particulate matter by means of the strip-off edge, to be fed to the coarse matter outlet. The remaining mixture of separator air and fine particulate matter is fed to the fine particulate matter outlet in a flow forming a sink. The present invention is based on the consideration that there is a risk in such cyclone separators that so-called spray particles will enter the fine particulate matter, already separated from the coarse matter, from the coarse matter located in front of the strip-off edge, so that the fine particulate matter will still contain a possibly small, but unintended percentage of coarse matter in the form of the above-mentioned spray particles. To eliminate this disadvantage, a coarsely separating separator wheel, which again separates the coarse matter component from the fine particulate matter by applying the centrifugal action, is arranged in the fine particulate matter outlet. Consequently, a high design expense is required in the form of the separator wheel merely to separate the small percentage of spray particles from the fine particulate matter. In addition, it is difficult to adjust the vanes of the stationary vane ring such that both the crude gas flow interspersed with the material to be separated in a well-dispersed form is introduced and good separation of the coarse matter from the fine particulate matter takes place. Only a compromise between these two requirements is possible, as a rule.